calculate index of array with multi dimensions.
your index will be parsed into the position of single dimension array.
thus, original array can carry, manipulate, clone and serialize easier.
// declare or reference your array for three-dimensions
const a = fromary([], [3, 3, 3]);
// access to get/set to its position in 1, 2, 2
a.set('item', 1, 2, 2)
a.get(1, 2, 2)